The following description of background art may include insights, discoveries, understandings or disclosures, or associations together with disclosures not known to the relevant art prior to the present invention but provided by the invention. Some such contributions of the invention may be specifically pointed out below, whereas other such contributions of the invention will be apparent from their context.
The evolvement of wireless cellular communications technologies and different services increase user needs to obtain over a wireless connection same broadband services that are obtained via a fixed connection. To fulfill both mobility requirements and increasing speed requirements, a solution called long term evolution (LTE), has been specified in 3GPP (Third Generation Partnership Project). LTE is a packet-only wideband radio access with flat architecture that provides higher data speeds and reduced packet latency and supports various services, such as high-speed data, multimedia unicast and multimedia broadcast services. One step in the evolution path towards fourth generation (4 G) cellular systems is a further development of LTE, called LTE-Advanced (LTE-A).
Relay nodes (RN) have been introduced to LTE-A to enhance coverage of high data rates, group mobility, temporary network deployment, a cell-edge throughput and/or to provide coverage in new areas. A relay node is an intermediate node between a donor base station (such as an enhanced node B, or advanced enhanced node B, i.e. DeNB) and a user equipment. Thus, there may be user equipments connected to the base station directly, and user equipments connected to the base station via the relay node. User equipments directly connected to the base station, so called macro user equipments, and the relay nodes are similar to the base station in many ways. For example, it has been suggested that measurements to be performed to support radio link operations, resource management, etc., should be performed in the same way regardless of whether the measurements relate to a relay node or to a macro user equipment or both of them in combination. However, characteristics relating to relay node usage may be different from those relating to serving macro user equipments.